Stretching clamp



March 1929. J. ZAGORSKI 1,706,972

STHETCHING CLAMP Filed March 24, 1927 2 Sheets-Sheet 1 Fig.1. a c 114 AA 1 I e '7 h B a l I 9 B b !A 9 c b d March 26, 1929. J. ZAGORSKI STRETCHING CLAMP I Filed March 24, 1927 2 Sheets-Sheet 2 Patented Mar. 26, 1929.

UNITED STATES 1,706,972 PATENT OFFICE.

JOHANN ZAGORSKI, OF FRANKFORT-ON-THE-MAIN, GERMANY, ASSIGNOR TO AMERI- CAN L'URGI CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

STBETCHIN G CLAMP Application filed March 24, 1927, Serial No. 178, 93, and in Germany March 24, 1926.

stretching clamps for aerial lines, making the clamp adapted for the straining of electric lines having the usual rope cross sec-- 6 tion or of electrical hollow conductors.

The hitherto used stretching clamps are rigid bodies, in which. the electric conductor is tightly clamped; the conductor can therefore not give way in the clamp even when vibrations are imparted to it for example by the pressure of wind or the like. This rigid clamping has the disadvantage, that such vibrations: act upon the electric conductor especially at the places lying shortly before or behind the stretching clamp. At

these places the conductor is therefore subjected to increased stress, which in certain cases may effect the break of the conductor.

The new stretching clamp according to the invention has the advantage over the former types, that the electric conductor in the stretching clamp may give way to a cer- .tain degree with respect to' the supporting body. This advantage is obtained by arranging a comparatively short clamping element for the conductor in such a manner in a supporting body connected to the insulating chain, that it is kept in this support essentially only by the pull of the rope.

A further advantage of the new stretching clamp consists, in that the conductor has not to be out 0d at the stretching place, but may lead away without interruption.

The invention is illustrated by way of example in the annexed drawing, in which Fig. 1 is the new stretching clamp partly in section,

Fig. 2 a modification serving at the same time as rope connector,

Fig. 3 a top view according to Fig. 1,

Figs. 4 and 5 are other modifications, and Figs. 6 and 7 are a side view andan end view, respectively, of a clamping sleeve.

Fig. 8 is an expanded view of the structure shown in Fig. 1.

The clamping element of the stretching head includes a bushing of two or several parts having a conical boring; the parts a and Z of said bushing are placed around the rope m and then connected by dove-tailing or similar connection. The bushing carries a split, conical lining 0, d, with rough, interior surface. Each part of the lining has several reciprocal slots, that is the slots extend alternately from each end towards the till opposite end. When inserting a rope the lining will then always suit itself exactly to the surface of the rope, thus distributing the pressure of the lining equally over the surface of the clamped rope piece. By a split nut e, f the stretching head is set on the rope with correspondingstrain. The stretching head is then set into the support in such a manner, that it is pressed by the pull of the rope against a corresponding surface of the support, so that it ma follow rotary movements of the rope. T e same giving way to rotary movements may evidently also be obtained by other similar arrangements of the stretching head in the support. By the action of the pull of the rope the lininge, f is drawn into the interior of the bushing a, I), thus automatically and concentrically clamping the conductor according to the strain acting upon it.

The support of the stretching clamp consists of a main part 9. Its frame like part includes a transverse Wall n which receives the stretching head and transfers the stress by its solid anchoring arms Z upon the stretching chains. The support of the stretching clamp is prolonged at both sides according to the sagging of the hollow conductor. The measures of the cross sections of these prolongations are corresponding to the dimensions of the hollow conductor, which thus finds a solid support, thereby preventing deformations.

On the side of the strained rope the channel guide for the support is at the .end at o slightly enlarged in vertical direction, thus giving the rope play when for example the sag is changing and-protecting it against damages. At the strainless side of the rope between the stretching clamps the guide for the support is slightly curved according to the wanted sag of the rope.

For the purpose of obtaining a round shape of the device without projecting edges the support is closed by a cover h, z and k.

consisting for example of three parts, which are put after the stretching head with the rope has been inserted. The division of the cover is shown in Fig. 1 by the interrupted lines BlB.

The bottom part of the support may remain open, whereby the assembling is facilitated; but it may also be closed.

The stretching head may also be constructed as rope connector, as shown in Fig.

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' ing p, by which the rope is pressed against the roughened, interior surface of the bushings 1' pushed over. These bushings r carry on their outer side left-handed and righthanded threads. By the sleeve 25 carrying a corresponding interior thread both the ends of the rope may be drawn together. This is sleeve t is in the same manner arranged in the frame 9 of the stretching clamp as the stretching head a, 6.

Another modification of the stretching clamp with respect to the transfer of the strain upon the stretching chains is shown in Figs. 4 and 5. The eyes a of both the arms Z of the frame 9 are passed by a alvanized steel tube 0, carrying on its en s caps w, secured in their position by threads or the like and suitably carrying the stretching clamps.

I claim:

1. In a stretching clamp for ropes and cables, a supporting body having anchoring arms extending laterally therefrom, a split bushing having one end seated against said supporting body, said bushing having a conical bore therethrough, and a split lining within said bore for clamping engagement with the cable.

2. In a stretching clamp, a split bushing having a conical bore, a split lining having an outer surface conforming to the said conical bore, a supporting body having a portion for rotatably supporting said bushing, and having anchoring arms carried by said body and spaced laterally from the line of the cable.

3. The invention as set forth in claim 2, in combination .with cover plates secured to said supporting body to give the same a smooth exterior surface.

4. In a stretching clamp, a yoke-shaped supporting body comprising lateral arms and a transverse wall portion, guide channels on said body at each side of said transverse wall for receiving a cable, the guide channel at the side of said body towards the strained cable being vertically enlarged, and a clamp fixed to the cable and rotatably seated against said transverse wall portion of the supporting body.

5. In a clamping device for attaching eonductors to supporting and tensioning members a conical clamping sleeve formed with a plurality of slots extending from opposite ends, and a hollow internally conical clamping head consisting of two interconnected longiutdinally divided partsfitting around said clamping sleeve.

6. In a clamping device for attaching conductors to supporting and tensioning members, a conical clamping sleeve formed with a plurality of slots extending from opposite ends, a hollow internally conical clamping head fitting around said clampin sleeve, and an annular nut screwing in said conical head and bearing against the broad end of said conical sleeve.

7. In a clamping device for attaching conductors to supporting and tensioning members, a conical clamping sleeve formed with a plurality of slots extending from opposite ends, a hollow internally conical clamping head consisting of two interconnected longitudinally divided parts fitting around said clamping sleeve, and an annular nut screwing in said conical head and bearing against the broad end of said conical sleeve.

8. In a clamping device for attaching conductors to supporting and tensioning mem bers, a conical clamping sleeve formed with a plurality of slots extending from opposite ends, a hollow internally conical clamping head consisting of two inter-dovetailed longitudinally divided parts fitting around said clamping sleeve.

9. In a clamping device for attaching conductors to supporting and tensioning members, a conical clamping sleeve formed with a plurality of slots extending from opposite ends, a hollow internally conical clamping head consisting of two inter-dovetailed longitiudinally divided parts iittting around said clamping sleeve, and an annular nut screwing in said conical head and bearing against the broad end of said conical sleeve.

10. In a stretching clamp for ropes and cables, a body having means for attachment to a support and having a transverse wall portion, a bushing rotatably seated against said wall portion and having a bore therethrough, and means including a split lining within said bore for clamping a cable to said rotatably mounted bushing.

11. Clamping device of the character de scribed for attaching conductors to supporting and tensioning members, comprising a conical clamping sleeve provided with a plurality of slots extending from opposite ends, a clamping casing adapted to receive said sleeve and provided with an abutment adapted to hold the larger conical head of said sleeve under the influence of the tension of the conductor.

12. Clamping device according to claim 11, 'in which the clamping sleeve rests rotatably in the casing so as to adapt itself to the movements of the conductor.

In testimony whereof, I aflix my signature.

J OHANN ZAGORSKI.

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